My parents have a raised ranch. Last year they had their master bathroom renovated and part of that was installing a new Panasonic WhisperCeiling fan/light/heater. Last night, out of curiosity, I went up in their attic since my Dad hasn't been up there since I was a child (I'm now 34, lol). I noticed someone installed the new bathroom fan using flexible ducting. The flex duct runs about 15 feet over the rafters then goes sharply upward and is tied to a 2x4 brace using extra pieces of 14 gauge NM. The end of the duct points towards the gable vent but it's about 2 feet away from it.
Is this even allowed by code? I thought bath fans need to exhaust to the outside?
What is the best way to fix this? I know best practice is to use rigid ducts with the shortest run. In this case they could either go out the roof or keep the long run, switch to rigid ducting wrapped with insulation, and install a dedicated vent lower in the gable wall. I didn't mention eves because they have soffit vents and running it out those would cause some of the humid air to come back in.
Here are pictures. Sorry for the poor quality but there wasn't much light and I had to use the zoom on my phone.
This is the bath fan. You can see part of the flex duct is crushed... almost seems like someone stepped on it.
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This is the end of the duct pointing towards the gable vent. You can also see the large bee/wasp nests at the top and bottom of the vent (yuck!).
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Is this even allowed by code? I thought bath fans need to exhaust to the outside?
What is the best way to fix this? I know best practice is to use rigid ducts with the shortest run. In this case they could either go out the roof or keep the long run, switch to rigid ducting wrapped with insulation, and install a dedicated vent lower in the gable wall. I didn't mention eves because they have soffit vents and running it out those would cause some of the humid air to come back in.
Here are pictures. Sorry for the poor quality but there wasn't much light and I had to use the zoom on my phone.
This is the bath fan. You can see part of the flex duct is crushed... almost seems like someone stepped on it.
This is the end of the duct pointing towards the gable vent. You can also see the large bee/wasp nests at the top and bottom of the vent (yuck!).
